The present invention generally pertains to communication networks and methods and is particularly directed to communication of control-function data to and from a plurality of user terminals in a full-mesh communication network.
In a communication network, such as a satellite communication network, it is desirable to communicate control-function data between a network control station and the user terminals while user-communication data is being communicated between the user terminals. User-communication data is data that users transmit to one another, such as audio, video, facsimile images, and data-processing data other than such as is used for network control functions. Control-function data includes data for performing network monitor and control functions and for providing the user terminals with command and control capability. The control functions include priority management and automatic power-level control. For example, the network control station should have the capability of being able to alter the communication network in accordance with the relative priority of user requests for different available communication channels in the network. Also, the network control station should have the capability of being able to probe any user terminal for the user-terminal operating status for the purpose of network management and the capability of being able to command the user terminals to adjust the power level to optimize the use of a satellite transponder when the network is a satellite communication network.
In a "star" type of communication network, in which communications between the user terminals are passed through a network-control-station terminal at the hub of the star network, the control-function data can be multiplexed with the user communication data in a common communication channel. However, in a full mesh communication network, in which there is no central hub for passing communications between the user terminals, the multiplexing scheme is not feasible because the communication channels dedicated to communicating user-communication data communicate the user-communication data directly between the user terminals. Thus, in a full-mesh network, an additional communication channel has been required for communicating control-function data between a network control station and a user terminal while the user terminal is communicating user-communication data directly to and from another user terminal over the dedicated communication channels. The use of an additional channel adds to the complexity and cost of each user terminal and reduces the number of channels available in the overall network bandwidth for communication of user-communication data, and thereby limits the applicability of a full-mesh network for satellite communications.